TRANSIMS
The TRansportation ANalysis and SIMulation System (TRANSIMS) is a set of travel modeling procedures designed to meet the State DOTs' and MPOs' need for more accurate and more sensitive travel forecasts for transportation planning and emissions analysis.
TRANSIMS outputs detailed data on travel, congestion, and emissions; information that is increasingly important to investment decisions and policy setting. Because TRANSIMS simulates and tracks travel by individuals, the benefits to and impacts on different geographies and travel markets can be evaluated as well. Furthermore, TRANSIMS has the capability to evaluate highly congested scenarios and operational changes on highways and transit systems.
TRANSIMS is based on four primary modules: population synthesizer, activity generator, route planner, and traffic microsimulator. Using these components, TRANSIMS estimates activities for individuals and households, plans trips satisfying those activities, assigns trips to routes, and creates a microsimulation of all vehicles, transportation systems, and resulting traffic in a given study area.
TRANSIMS differs from previous travel demand forecasting methods in its underlying concepts and structure. These differences include a consistent and continuous representation of time; a detailed representation of persons and households; time-dependent routing; and a person-based microsimulator. These advances are producing significant changes in the travel forecasting process. To date the TRANSIMS models have been tested with data from Dallas, Texas, and Portland, Oregon.
TRANSIMS has been developed by researchers at the Los Alamos National Laboratory and is available commercially through the IBM TRANSIMS Solution Center. The design for TRANSIMS is based on requirements in the Intermodal Surface Transportation Efficiency Act, the Transportation Equity Act for the 21st Century and Clean Air Act Amendments. The development of TRANSIMS has been funded by the Federal Highway Administration, the Federal Transit Administration and the Office of the Assistant Secretary for Transportation Policy of the United States Department of Transportation, and by the Environmental Protection Agency.
More information on TRANSIMS can be found on the TRANSIMS Open Source site.